Generating duplicated classes when object is reference more than once

[Emad89]

Generated classes are duplicated in the following situation:

If object A is referenced as a response in API_endpoint1, And object B iis referenced as a response API_endpoint2, where B has a property that references A. When resolving paths:

• The relatvice path for object A resolved from API_endpoint1 looks like this: ./../A.

• The relatvice path for the same object A resolved from object B looks like this: ../A.

In this scenario, the presence of both ./ and ../ can lead to the creation of duplicated objects.

[Emad89]

I quick work around is to condsider ./../A is the same as ../A, here is a PR to add this check [PR] (https://github.com/swagger-api/swagger-parser/pull/2015)